function dot#save(source)
    let l:target=input('save to file :',fnamemodify(a:source,":p:r").'.'.g:dotInfo['type'],'file')
    if l:target == '' 

    else
        let l:dir=fnamemodify(l:target,':p:h')
        if !isdirectory(l:dir)
            call mkdir(l:dir)
        endif
        let l:cmd= g:dotInfo['algorithm']." ". a:source . " -T".g:dotInfo['type']." -o ".l:target
        if exists("g:debug.func")
            echo l:cmd
        endif
        let g:a=l:cmd
        call python#execute_os_cmd(l:cmd)
    endif
    return l:target
endfunction

let s:loaded_driver=0
let s:dir= expand("<sfile>:p:h").'/'



